Burner for a heater

ABSTRACT

The present invention provides a burner ( 10 ) for a heater for combustion of a hydrocarbon liquid. The burner ( 10 ) comprises a combustion chamber having a combustion zone ( 17 ) for combusting the hydrocarbon liquid and at least one tank portion ( 13, 15 ) for containing an amount of the hydrocarbon liquid. The or each tank portion ( 13, 15 ) is positioned adjacent the combustion zone ( 17 ) and arranged to feed the hydrocarbon liquid into the combustion zone ( 17 ). The or each tank portion ( 13, 15 ) is at least in part filled with a filling material having a plurality of portions that pass through the interior of the or each tank portion ( 13, 15 ).

FIELD OF THE INVENTION

The present invention broadly relates to a burner for a heater. Theburner is arranged for combustion of a hydrocarbon liquid.

BACKGROUND OF THE INVENTION

Traditionally, heating of buildings such as private homes involves gas,oil, wood and electric heaters. Generally, wood heaters have thedisadvantage that a flue is required for exhaust fumes and that the woodneeds to be stored. In many dwellings such as apartments, units andtownhouses installation of a flue and storage of the wood may causeproblems or may not be possible at all. Gas heaters have similarproblems as a gas connection is required. Oil heaters also need to beflued. Electrical heaters are generally rather expensive to operate andrequire electrical connections.

One interesting and largely environmentally clean alternative is aheater that is arranged for combustion of a hydrocarbon liquid such asan alcohol. For example, if ethanol is combusted, the exhaust productsare largely limited to carbon dioxide and water steam.

A simple burner for ethanol has previously been used to provide a heatsource for a fireplace. This burner comprises an open tank in whichethanol is combusted. However, as ethanol and other hydrocarbon liquidsare easily combustible and may even be explosive if in vapour form ormixed with air, there is a need for a burner for a hydrocarbon liquidthat provides improved safety.

SUMMARY OF THE INVENTION

The present invention provides in a first aspect a burner for a heaterfor combustion of a hydrocarbon liquid, the burner comprising:

a combustion chamber having a combustion zone for combusting thehydrocarbon liquid and at least one tank portion for containing anamount of the hydrocarbon liquid, the or each tank portion beingpositioned adjacent the combustion zone and being arranged to feed thehydrocarbon liquid into the combustion zone, the or each tank portionbeing at least in part filled with a filling material having a pluralityof portions that pass through the interior of the or each tank portion.

A combustible gas over the surface of the hydrocarbon liquid typicallyneeds to have a temperature above a threshold value to ignite. Thefilling material typically is arranged for distribution of at least someof the heat that is in use developed in the combustion zone and directedinto the or each tank portion whereby local heat maxima in the tankportion are reduced and thereby likelihood of ignition in the tankportion is reduced. Further, as typically burning of the hydrocarbonliquid in the tank portion is avoided, fuel efficiency is alsoincreased.

For example the filling material may comprise a large number, such asmore than one hundred or more than one thousand particles which definespaces between them. Alternatively, the filling material may comprise amesh or gauze such as a mesh or gauze of wires or fibres or a metallicwool such as steel wool. The filling material may comprise a metallicmaterial, a plastics material, a mineral or any other suitable material.The steel wool may be stainless steel wool which has superior corrosionproperties compared with conventional steel wool.

The heater may be a heater for heating at least a portion of a buildingsuch as a commercial space or a home. For example, the burner may form apart of a fireplace.

The burner typically comprises a combustion control means forcontrolling gas exchange of the combustion in the combustion zone.

For example, the control means may comprise an opening that allowsdiffusion of oxygen into the combustion chamber and a closure for theopening. This particular arrangement has the advantage that operation ofthe flame of the burner may be extinguished at any time by simplyclosing the opening and thereby interrupting the supply of oxygenrequired for the combustion. This feature therefore provides a furthersignificant safety advantage.

The control means may also be arranged to regulate the oxygen diffusioninto the combustion chamber so as to regulate the combustion propertiesof the burner. This feature therefore allows the regulation of the heatand flame output and of the consumption of the hydrocarbon liquid.

For example, the combustion control means may comprise a shutter that isarranged to adjust the opening and/or close the opening so thatcombustion may be controlled and/or to extinguish a flame in thecombustion zone. The combustion chamber may comprise a lid portion inwhich the opening is positioned and the shutter may be arranged to slideacross the opening of the lid portion. The shutter typically is guidedby a guide and moveable relative to the opening typically in a straightdirection. The shutter may also be connected to the combustion chamberby a hinge that allows the sliding movement. In this case, the hinge maybe arranged for movement about a vertical axis.

Alternatively, the shutter may be moveable relative to the opening in adirection that has a vertical component. In this case the hingetypically is arranged for movement about a horizontal axis.

The shutter may be positioned inside the combustion chamber and may bearranged for sliding across an inner surface of the lid portion. In aspecific embodiment the shutter and the lid portion are arranged so thatthe shutter may not interfere with objects located on the burner.Further, a mechanism that may be associated with the shutter may bepositioned so that it cannot easily be accessed from the outside of thecombustion chamber which further improves the safety of the burner.Further, the shutter may comprise rollers which are guided by guides inthe lid portion and which improve the smoothness of the sliding motionwhen the shutter is moved and thereby reduce likelihood of sparkformation.

In order to reduce the likelihood of jamming of the shutter, a portionof the shutter that in use is in contact with the lid portion maycomprise a material that is softer than the lid portion which itcontacts. In one specific embodiment the shutter is arranged so that,when the opening is closed, the lid portion overlaps the shutter.Because of the overlap, the likelihood of oxygen diffusion into thecombustion chamber with an amount sufficient for combustion is furtherreduced which further improves the safety of the burner. Further, theshutter may comprise a handle portion that in use projects through aslot of the lid portion and the burner may be arranged so that movementof the handle portion along the slot effects sliding of the shutteracross the opening of the lid portion. The chamber may be configuredsuch that oxygen diffusion through the slot is substantially inhibited.

The combustion chamber may comprise stainless steel and the softermaterial may be brass. Spacers may be positioned at an external portionof the burner arranged for positioning between the burner and an itemthat supports the burner so that direct contact of the burner with theitem is avoided and the item may comprise a combustible material such asa timber material. For example, the burner with the spacers may bearranged for positioning in the combustible material. The burner mayalso comprise a tray in which the burner is positioned and which isarranged to avoid direct contact with the combustible material.

The heater typically is arranged for positioning in an item so that atleast a portion of the burner is positioned below a surface of the item.For example, the heater may be arranged for positioning in the item sothat the surface of the item is approximately at the same level as a topportion of the combustion chamber. The heater may be arranged forpositioning in a fireplace or any other building portion or in afurniture item such as a table. The heater typically does not have anyconnections such as fuel lines and typically is arranged for manualrefilling. This has the particular advantage that it is relatively easyto install the heater in a building. Further, typically no flue isrequired.

The combustion chamber may comprise a fuel inlet opening through whichthe hydrocarbon liquid may be filled into the or each tank portion ofthe combustion chamber. The fuel inlet opening is typically remote fromthe opening of the combustion control means.

Further, the fuel inlet opening may comprise a closure, such as ashutter, and the burner may be arranged so that, when the shutter of thecombustion control means is fully open, the shutter of the fuel inletopening is closed and only when at least a portion of the shutter of thecombustion control means is closed the fuel inlet opening is fully open.In a specific embodiment the shutter of the combustion control means andthe shutter of the fuel inlet means are provided in form of an integralpart.

The fuel inlet opening may also comprise a grid through which thehydrocarbon liquid is filled into a tank portion. The grid functions toreduce the likelihood of formation of air pockets in the hydrocarbonliquid during filling and formation of air bubbles when the fuel isfilled into the tank portion.

In a specific example the combustion chamber comprises two tank portionsbetween which the combustion zone is positioned. In this example thecombustion zone is located underneath the opening of the combustioncontrol means. The tank portions are separated from the combustion zoneby wall portions that comprise apertures to allow the fuel to penetratefrom the tank portions into the combustion zone.

The burner may be arranged for the combustion of any hydrocarbon liquidincluding any type of alcohol. In a specific embodiment the burner isarranged for the combustion of ethanol or methylated spirits which hasthe advantage that the combustion is largely environmentally friendly.

The present invention provides in a second aspect a heater comprisingthe above-defined burner.

The present invention provides in a third aspect a a heater forcombustion of a hydrocarbon liquid, the burner comprising:

a combustion chamber having a combustion zone for combusting thehydrocarbon liquid and at least one tank portion for containing anamount of the hydrocarbon liquid, the or each tank portion beingpositioned adjacent the combustion zone and being arranged to feed thehydrocarbon liquid into the combustion zone,

and a fuel inlet portion having a closure, and

a combustion control means for controlling gas exchange of thecombustion zone through an gas exchange opening of the combustionchamber

wherein the closure of the fuel inlet opening is arranged so thatfilling of the fuel into the or each tank portion is only possible ifthe combustion control means closes at least a portion of the gasexchange opening of the combustion chamber.

The combustion control means typically comprises a shutter forcontrolling the gas exchange through the gas exchange opening of thecombustion chamber. The closure of the fuel inlet opening typically alsoincludes a shutter. Typically the shutter for controlling gas and theshutter of the fuel inlet opening are coupled and may also be integrallyformed.

The invention will be more fully understood from the followingdescription of a specific embodiment. The description is provided withreference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is (a) a side-view, (b) a further side-view, (c) a top-view and(d) a perspective view of a burner for a heater according to a specificembodiment,

FIG. 2 is a perspective and exploded view of components of the burnershown in FIG. 1.

DETAILED DESCRIPTION OF A SPECIFIC EMBODIMENT

Referring to FIGS. 1 and 2 the burner for a heater according to aspecific embodiment is now described. In this embodiment the burner 10comprises a lid portion 12 and a body portion 14. The lid portion 12 andbody portion 14 are composed of stainless steel. The lid portion 12 hasan opening 16 below which the combustion zone 17 of the burner islocated.

In this embodiment, the combustion zone 17 is positioned between twotank portions 13 and 15 of the burner and stainless steel walls 18 and20 separate the tank portions 13 and 15 from the combustion zone 17. Thewalls 18 and 20 have apertures 19 which allow the hydrocarbon liquid topenetrate from the tank portions 13 and 15 into the combustion zone 17.The tank portions 13 and 15 are filled with stainless steel wool (notshown) which distributes heat and reduces likelihood of ignition in thetank portions 13 and 15 and thereby reduces formation of air pocketswithin the hydrocarbon liquid. It will be appreciated that inalternative embodiments the burner may take any other suitable form. Forexample, the burner may comprise one or more than two tank portions.

Further, the tank portions may be filled with any material that conductsheat and that allows fuel to be stored in the tank portions. Alternativeexamples any type of metal wool (not necessarily stainless) and a largenumber of small particles such as metal balls. Further the material withwhich the tank portions are filled may not necessarily be metallic butmay comprise a non-metallic material.

In this embodiment, the burner 10 is arranged for the combustion ofethanol or methylated spirits which has the advantage that thecombustion is largely environmentally friendly.

The burner also comprises a shutter 22 that is guided by guides 24 and26. The shutter 22 has a handle portion 28 that projects through a slot30 of the lid portion 12. By moving the handle portion 28 along the slot30 the shutter adjusts the opening 16 and thereby controls the exchangeof oxygen and exhaust through the opening 16 (and also controls theconvection of oxygen within the combustion chamber). This allows tocontrol heat output of the burner and the fuel consumption. Further, theshutter may fully close opening 16 so that the penetration of oxygeninto the combustion chamber is substantially stopped whereby the flamein the combustion zone is extinguished. The shutter 22 is larger thanthe opening 16 so that in a closed position the shutter 22 overlaps lidportion 12 from the inside and, due to the overlap, the likelihood ofdiffusion of an amount of oxygen into the combustion chamber that issufficient for combustion is further reduced.

Wall portion 18 comprises a flat portion 32 which has a recess portion34 positioned underneath handle portion 28 and slot 30 so as to preventdiffusion of oxygen through the slot into the interior of the burner 10.In this embodiment the shutter 22 comprises brass rollers (not shown)which are received by guides 24 and 26 so that during sliding of theshutters the rollers roll in guides 24 and 26 which reduces friction.Further, as the rollers are composed of brass which is a soft material,likelihood of jamming is reduced.

It will be appreciated that in alternative embodiments the shutter maytake any other form and shape. For example, the shutter may be hingetlyconnected to the body portion 14 or to the lid 12 portion.Alternatively, the shutter may be a lid that is removable from the bodyportion lid.

The lid portion 12 comprises a fuel inlet opening 35 which has aninternal grid (not shown) through which during a fuel filling processfuel penetrates and which reduces likelihood of formation of air pocketsin the fuel. The shutter 22, the opening 34 and the opening 16 arearranged so that, when shutter 22 opens fuel inlet opening 35, theshutter 22 closes at least a portion of opening 16 and thereby reducesthe flame in the combustion zone which improves the safety duringfilling the hydrocarbon liquid into the burner 10. Further, fuel inletopening 35 has a lid 36 and in this specific embodiment wall 20 has ascale that functions as a fuel level indicator.

In this embodiment the burner is largely composed of stainless steel(the exception being the brass rollers of the shutter 22) which resistscorrosion. However, in variations of the embodiment the burner may becomposed of any other suitable metallic or non-metallic material and mayalso comprise ceramics materials.

The body 14 has a V-shaped bottom portion 38 and therefore gravitypermits the direction of the hydrocarbon liquid to the combustion zone.The lid portion 12 has lips 40 and 42 which are arranged to be slidinglyreceived by the interior of the body portion 14 and thereby provide alargely oxygen diffusion tight connection with the body portion 14.

The burner 10 may also comprise spacers (not shown) such as bracketsthat allow the burner to be installed into a combustible medium such asa timber plate. In this case the spacers may be arranged to inhibitdirect contact of the combustion chamber and the combustible medium. Theburner 10 typically is arranged for insertion into a cavity of an itemsuch as a portion of a building, eg a fire place, or a furniture itemsuch as a table. Typically an upper edge of the burner 10 is flush witha surface of the item.

Although the invention has been described with reference to particularexamples, it will be appreciated by those skilled in the art that theinvention may be embodied in many other forms. For example, the burnermay be arranged for the combustion of any hydrocarbon liquid. Further,the burner may have any volume, size and shape including for exampleround, rectangular and triangular shapes.

1. A burner for a heater for combustion of a hydrocarbon liquid, theburner comprising: a combustion chamber having a combustion zone forcombusting the hydrocarbon liquid and at least one tank portion forcontaining an amount of the hydrocarbon liquid, the or each tank portionbeing positioned adjacent the combustion zone and being arranged to feedthe hydrocarbon liquid into the combustion zone, and a fuel inletportion having a closure; and a combustion control means for controllinggas exchange of the combustion zone through an gas exchange opening ofthe combustion chamber, wherein the burner is arranged so that the fuelinlet opening is only fully open when the combustion control meanscloses at least a portion of the gas exchange opening of the combustionchamber.
 2. The burner as claimed in claim 1 wherein the combustioncontrol means comprises a shutter for controlling the gas exchangethrough the gas exchange opening of the combustion chamber.
 3. Theburner as claimed in claim 2 wherein the shutter for controlling gasalso is arranged for closing the fuel inlet opening.
 4. A burner for aheater for combustion of a hydrocarbon liquid, the burner comprising: acombustion chamber having a combustion zone for combusting thehydrocarbon liquid and at least one tank portion for containing anamount of the hydrocarbon liquid, the or each tank portion beingpositioned adjacent the combustion zone and being arranged to feed thehydrocarbon liquid into the combustion zone, the or each tank portionbeing at least in part filled with a filling material having a pluralityof portions that pass through the interior of the or each tank portion;a combustion control means for controlling gas exchange of thecombustion in a first combustion zone, the control means comprising anopening that allows diffusion of oxygen into the combustion chamber anda shutter that is arranged to adjust the opening so as to control thecombustion the combustion zone; and a fuel inlet opening for filling thehydrocarbon liquid into the burner, wherein the filling material isarranged for distribution of at least some of the heat that is developedin the combustion zone and is directed into the or each tank portionwhereby at least one local heat maximum in the tank portion is reduced,thereby reducing the likelihood of ignition in the tank portion, andwherein the burner is arranged so that, when the shutter of thecombustion control means is fully open, the fuel inlet opening is closedand only when at least a portion of the combustion control means isclosed, the fuel inlet opening is fully open.
 5. The burner of claim 4wherein the burner is arranged so that when the shutter of thecombustion control means is fully open, the shutter of the combustioncontrol means closes the fuel inlet opening and only when at least aportion of the shutter of the combustion control means is closed, thefuel inlet opening is fully open.
 6. A burner for a heater forcombustion of a hydrocarbon liquid, the burner comprising: a combustionchamber having a combustion zone for combusting the hydrocarbon liquidand two tank portions for containing an amount of the hydrocarbonliquid, the combustion zone being positioned between the tank portionsand the tank portions being arranged to feed the hydrocarbon liquid intothe combustion zone, the tank portions being at least in part filledwith a filling material having a plurality of portions that pass throughthe interior of the tank portions, wherein the filling material isarranged for distribution of at least some of the heat that is developedin the combustion zone and is directed into the tank portions whereby atleast one local heat maximum in the tank portions is reduced, therebyreducing the likelihood of ignition in the tank portions and wherein thetank portions are separated from the combustion zone by wall portionsthat comprise apertures to allow the fuel to penetrate from the tankportions into the combustion zone.